The present invention relates generally to invasive medical probes and methods, and specifically to intravascular catheterization and catheterization techniques.
Catheterization procedures are very commonly performed for diagnosis and treatment of diseases of the heart and vascular system. The catheterization procedure is generally initiated by inserting a guide wire into a blood vessel in the patient""s body. The guide wire is then guided to the desired location, most commonly in one of the heart vessels or elsewhere in the vascular system. At this point the catheter is slid over the guide wire into the blood vessel and/or heart. Once the catheter is in the desired position, the guide wire can then be removed, leaving the catheter in location. Alternatively, in some procedures, the catheter is inserted without using a guide wire. The catheter may be used to pass ancillary devices into the body, such as an angioplasty balloon, or to perform other diagnostic or therapeutic procedures.
In order to facilitate the guide wire insertion and the subsequent catheter application, the physician generally performs the procedure with the assistance of a fluoroscope, as is well known in the art. The fluoroscope produces a real-time image showing the continued progress of the guide wire, or the catheter, through the patient""s body.
The fluoroscope generates a high level of X-ray radiation, which poses a significant danger to medical personnel exposed thereto, as is well known in the art. In order to provide protection from radiation exposure, the attending medical personnel generally wear a heavy, cumbersome protective lead garment which covers the entire body and neck, or use various lead shields including transparent glass face and eye shields.
It is an object of some aspects of the present invention to provide apparatus and methods of catheterization that allow medical personnel to be distanced from the vicinity of the fluoroscope and its resultant radiation, thereby reducing radiation exposure of the personnel.
It is a further object of some aspects of the present invention to provide a mechanism for remote control performance of catheterization procedures.
In preferred embodiments of the present invention, a remote control catheterization system feeds an intravascular catheter into the body of a patient. The system is preferably used to perform substantially all aspects of a catheterization procedure, including insertion of a guide wire in preparation for catheter insertion and therapeutic and/or diagnostic treatments using the catheter. The system is operated by a physician who observes a fluoroscopic image of the procedure on a remote fluoroscope screen, preferably outside the room in which the patient is located, and controls the procedure using a remote control console.
In some preferred embodiments of the present invention, the physician inserts a cannula into the patient""s blood vessel and inserts a guide wire through the cannula into the body, in a manner known in the art. The proximal portion of the guide wire is fed through a propelling device, which feeds the guide wire into the vessel while providing steering and speed control. The propelling device is controlled by the physician using the remote control console.
Once the guide wire has been inserted to a desired location, for example within a coronary artery, the physician passes a catheter over the proximal end of the guide wire. The proximal portion of the catheter is then placed in the propelling device, which feeds the catheter over the wire, similarly under the physician""s control using the console. The feeding device may then be used similarly to control the catheter inside the body and to pass ancillary devices, such as an angioplasty balloon, through the catheter.
In some preferred embodiments of the present invention, the propelling device comprises one or more propelling mechanisms, preferably three such mechanisms, one for each of the guide wire, catheter and ancillary device. In one such preferred embodiment, each of the propelling mechanisms comprises two wheels, preferably fabricated from a rigid non-corrosive material, such as PVC. The distance between the wheels is adjustable to the accommodate the width of the guide wire, catheter or ancillary device, as applicable. The wheels are driven by a small motor, as is well known in the art, which is controlled by the physician using the remote control console.
Although it is most convenient to use three separate propelling mechanisms, in an alternative preferred embodiment of the present invention, the propelling device comprises only one propelling mechanism. The sole propelling mechanism comprises two adjustable wheels as described above, a motor, and applicable gauges. Once the guide wire has been inserted to a desired position within the body, the guide wire is removed from between the wheels of the propelling mechanism, and the catheter or ancillary device is threaded into the propelling mechanism, as applicable.
In other preferred embodiments of the present invention, the propelling mechanism may comprise a robot arm, or any other suitable manipulation mechanism known in the art.
In preferred embodiments of the present invention, the physician receives feedback, preferably both tactile and visual feedback, indicative of the force needed to insert the guide wire, catheter or ancillary device. This feedback alerts the physician if an obstruction or other obstacle has been encountered. In the preferred embodiment described above, torque gauges are preferably coupled to the motor to measure the reverse force applied to the guide wire, catheter or ancillary device during insertion, and thus provide the feedback. Additionally, a rotor gauge is preferably coupled to the guide wire, catheter or ancillary device to measure and verify its speed of advance.
Preferably, the torque gauges or other force-measuring devices are coupled to a safety mechanism, which halts the insertion if the gauge reaches a predetermined force threshold.
The torque measurement, along with the measured speed, are relayed to the remote console situated outside of the catheterization room. The physician at the console thereby has at his command substantially all the information needed to control the procedure: the fluoroscope display, the reverse force measurement, and the measurement of the advance speed. This information enables the physician to perform the guide wire insertion, as well as catheter insertion and other diagnostic or therapeutic procedures, as applicable, via remote control, substantially without exposure to X-ray radiation.
In some preferred embodiments of the present invention, the remote control console comprises a steering device, preferably a joystick. The speed and direction of motion of the propelling device are controlled by the direction and extent to which the physician displaced the joystick from its center, xe2x80x9czeroxe2x80x9d position. Preferably, the reverse force measurement is fed back to the joystick, so that the greater the resistance encountered by the guide wire, catheter or ancillary device, the greater is the force required to displace the joystick.
Although preferred embodiments are described herein with reference to cardiac catheterization procedures, it will be appreciated that the principles of the present invention may similarly be applied to other medical procedures that are performed using fluoroscopic visualization, for example, non-cardiac catheterization or angioplasty, and other radiological procedures involving the use of catheters under fluoroscopy.
There is therefore provided, in accordance with a preferred embodiment of the present invention, a remote control catheterization system including:
a propelling device, which controllably inserts a flexible, elongate probe into the body of a patient; and
a control console, in communication with the propelling device, and including user controls which are operated by a user of the system remote from the patient to control insertion of the probe into the body by the propelling device.
Preferably, the propelling device includes wheels which roll against the elongate probe in one direction to advance the elongate probe, and in the reverse direction to retract the elongate probe. Alternately or additionally, the propelling device includes an arm which grasps and pushes the probe to advance it, and grasps and pulls the probe to retract it.
Preferably, the propelling device includes a rotating mechanism, which rotates the probe about a longitudinal axis thereof. Preferably, the rotating mechanism includes rollers which roll against the elongated probe.
Preferably the propelling device includes a motor which drives the insertion of the probe.
Preferably, the propelling device includes a force sensor which measures a force applied during insertion of the elongate probe, most preferably, including a torque gauge which measures a torque required to move the elongate probe.
Preferably the control console receives force measurements from the force sensor and provides tactile feedback responsive thereto to the user.
Preferably the propelling device includes a movement sensor for measuring a linear advance of the elongate probe.
Preferably, the system includes a fluoroscope which produces a real-time image showing the progress of the elongate probe in the patient""s body, which is displayed on the control console. Most preferably, the console includes a display which receives and displays data relating to the propelling device.
Preferably, the user controls includes a joystick for tactile control of the propelling device.
There is additionally provided, in accordance with a preferred embodiment of the present invention, a method for catheterization including:
inserting an elongate, flexible probe into a body passage;
feeding a portion of the probe outside the body into a propelling device, which advances the probe through the body passage; and
controlling the propelling device to advance the probe from a location remote from the body.
Preferably, feeding the portion of the probe includes feeding the probe between wheels which roll against the probe to advance it. Additionally or alternately, feeding the portion of the probe includes grasping the probe with an arm which pushes the probe to advance it.
Preferably, feeding the portion of the probe includes feeding the probe into a rotating mechanism, which rotates the probe about a longitudinal axis thereof, most preferably including feeding the probe between rollers which roll against the probe to rotate the probe around its longitudinal axis.
Preferably, controlling the propelling device includes controlling a motor which drives the insertion of the elongate probe.
Preferably, controlling the propelling device includes measuring a force applied to move the elongate probe, most preferably by measuring a torque.
Preferably, controlling the propelling device includes measuring a linear advance of the elongate probe.
Preferably, controlling the propelling device includes displaying a fluoroscopic image showing progress of the elongate probe in the patient""s body.
Preferably, controlling the propelling device includes receiving measurements relating to the propelling device and displaying the measurements on the control console. Preferably, controlling the propelling device includes operating a joystick, most preferably, including receiving tactile feedback relating to the propelling device.
Preferably, inserting the elongate probe includes inserting a guide wire and inserting the elongate probe over the guide wire. Additionally or alternatively, the method includes inserting an ancillary device through the elongate probe.
Preferably, inserting the elongate probe includes inserting a catheter into a blood vessel.
In a preferred embodiment, controlling the propelling device includes controlling the device to advance the catheter to the heart.